Polar bear vs grizzly bear size: which is bigger?

On the Arctic coast of Canada, where tundra meets sea ice, a grizzly and a polar bear sometimes cross paths. Side by side, one looks long and pale, the other brown and humped. But which one is really bigger?

Polar bears are bigger. An adult male polar bear usually weighs 350 to 590 kg (772 to 1,300 lb), says Polar Bears International. Adult male grizzlies in the lower 48 US states average 400 to 600 lb (about 180 to 270 kg), says the US Fish and Wildlife Service. Only big coastal brown bears come close.

Polar bear vs grizzly bear size: how do they compare?

The polar bear wins on almost every measure. Males outweigh male inland grizzlies by roughly two to one, polar bears are longer, and a standing male polar bear is about 30 cm taller than even a very large brown bear. “Grizzly” here means inland North American brown bears, so coastal Alaskan brown bears get their own row.

Polar bear vs grizzly bear: male and female size compared

Measure	Polar bear	Grizzly bear (inland brown bear)
Adult male weight	350–590 kg (772–1,300 lb) (PBI)	Average 400–600 lb (about 180–270 kg), lower 48 US (FWS)
Adult female weight	150–295 kg (331–650 lb) (PBI)	Average 250–350 lb (110–160 kg), lower 48 US (FWS)
Coastal brown bears	Not applicable	Coastal southern Alaska: males average 389 kg (858 lb), females 207 kg (456 lb); some males up to 780 kg (ADW)
Head and body length	Males 2.4–2.6 m (7.9–8.5 ft); females 1.9–2.1 m (6.2–6.9 ft) (SDZWA)	About 1.5–2.1 m (5–7 ft) (NPS)
Height at the shoulder	Usually 1–1.5 m (3.3–4.9 ft) (WWF)	About 0.9–1.5 m (3–5 ft) (NPS)
Height standing on hind legs	About 3 m (10 ft) for males (PBI)	Almost 2.7 m (9 ft) for very large bears (NPS)
Tail	7–12 cm (3–5 in) (SDZWA)	6–20 cm (2–8 in) (SDZWA, brown bear)
Front claws	Short and curved	Very long, 5–10 cm (2–4 in) (SDZWA)

No source we checked gives separate male and female heights for either bear, so heights in the table cover adults of both sexes.

Which is heavier, a polar bear or a grizzly?

The polar bear, for both males and females. A male polar bear usually weighs 350 to 590 kg (772 to 1,300 lb), while male grizzlies in the lower 48 US states average about 180 to 270 kg (400 to 600 lb). Females follow the same pattern: 150 to 295 kg for polar bears against 110 to 160 kg for grizzlies.

Pregnant polar bears get heavier still, at more than 453 kg (1,000 lb) before denning, says San Diego Zoo Wildlife Alliance. Grizzly weights shrink further north and inland: brown bears in southwestern Yukon average only 140 kg, says Animal Diversity Web. See how big a polar bear is and how much a grizzly bear weighs.

Which is taller when standing up?

The polar bear. A big male stands about 3 m (10 ft) tall on his hind legs, says Polar Bears International. Very large brown bears reach almost 2.7 m (9 ft), says the National Park Service, and most inland grizzlies are smaller than that. On all fours the gap is smaller.

WWF says adult polar bears are usually 1 to 1.5 m (3.3 to 4.9 ft) at the shoulder, and the NPS gives brown bears about 0.9 to 1.5 m (3 to 5 ft). Polar bears also have longer necks and bodies, so they look long and low. Grizzlies look chunkier, with a big shoulder hump.

Are polar bears bigger than grizzly bears everywhere?

Not always. Brown bears on the coast of southern Alaska grow huge. Males there average 389 kg (858 lb) and some reach 780 kg, says Animal Diversity Web. That matches or beats an average male polar bear. The fair answer: polar bears are bigger on average, but the biggest coastal brown bears overlap with them.

The US Fish and Wildlife Service gives Kodiak males 272 to 635 kg (600 to 1,400 lb). Our pages on the Kodiak bear and the biggest bear in the world look at the record holders.

Are polar bears and grizzly bears the same species?

No, but they are close cousins. Grizzlies are brown bears, Ursus arctos; the National Park Service explains that “grizzly” usually means brown bears living inland. Polar bears are a separate species, Ursus maritimus. They are close enough to have cubs together; read the story in grizzly polar bear hybrids.

What roles do these two big bears play in nature?

Both are big predators, but in very different worlds. Polar bears are a top carnivore of the Arctic, and leftover seal kills feed young bears and Arctic foxes, says Animal Diversity Web. Brown bears are important predators and seed dispersers where they live (ADW). Compare what polar bears eat with what grizzly bears eat.

How can you tell a polar bear from a grizzly?

Colour is the obvious clue, but not the only one. Grizzlies have a distinct shoulder hump and very long front claws of 5 to 10 cm (2 to 4 in), says the San Diego Zoo brown bear fact sheet. Polar bears have no hump, a longer neck and a narrower head. If you ever see either in the wild, give it lots of space and follow local bear safety rules.

Myths about polar bear and grizzly size

Myth: Grizzlies are the biggest bears.

Fact: San Diego Zoo Wildlife Alliance says the grizzly is one of the smallest brown bear subspecies. Why people believe it: its fierce reputation and the huge coastal brown bears that get photographed most.

Myth: A polar bear is always bigger than any brown bear.

Fact: Coastal Alaskan males average 389 kg and can reach 780 kg (ADW), overlapping with polar bears. Why people believe it: comparisons often use inland grizzlies only.

Test yourself

1. Which bear is usually heavier, a male polar bear or a male grizzly?

The male polar bear, roughly twice as heavy as a lower-48 grizzly.

2. How tall can a very large brown bear stand?

Almost 2.7 m (9 ft), says the National Park Service.

3. Which body feature helps you spot a grizzly?

Its shoulder hump, plus very long front claws.

Frequently asked questions

Sources

1. Polar Bears International. Polar bear facts.
2. San Diego Zoo Wildlife Alliance Library. Polar bear fact sheet: physical characteristics.
3. San Diego Zoo Wildlife Alliance. Polar bear.
4. San Diego Zoo Wildlife Alliance. Brown bear.
5. San Diego Zoo Wildlife Alliance Library. Brown bear fact sheet: physical characteristics.
6. US Fish and Wildlife Service. Grizzly bear.
7. US Fish and Wildlife Service. Kodiak brown bear.
8. National Park Service. Brown bears.
9. Animal Diversity Web, University of Michigan. Ursus arctos.
10. Animal Diversity Web, University of Michigan. Ursus maritimus.
11. WWF-UK. Polar bears.
12. CDC National Center for Health Statistics. FastStats: body measurements.

Sources checked 12 October 2026.